Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only either as two by three or three by two blocks.
A146154
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only either as two by three or three by two blocks.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =1a(6) =10a(7) =10a(8) =43a(9) =65a(10) =310a(11) =319a(12) =2668a(13) =3017a(14) =34910a(15) =54223a(16) =689528a(17) =1137739a(18) =18655423a(19) =31210424a(20) =700220638a(21) =1365782613a(22) =38696080322a(23) =86209219516
External references
- oeis: A146154